Anxiety can be caused by many things, can be a symptom of several conditions that can mimic e a variety of somatic ( physical) symptoms including chest pain.

Anxiety too can impact your life & your being. It responds to treatment which may include various forms of supports, talk therapy and /or medication. See your doctor,decide together if further tests are needed & get the help you deserve
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Caffiene and psycho stimulants have similar effects raising heart rate/blood pressure ,helping people feel more focused but potentially interfering with sleep.

Psychostimulants are prescribed to treat attention deficit disorder with or without hyperactivity. Caffeine + meds are additive .Too much can make people feel irritable , agitated with GI upset ( nausea) . See how it affects you .
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The most effective treatment is psychotherapy , ps, particularly cognitive-behavioral therapy (CBT). Medications that treat anxiety such as the SSRI ( For example Prozac , lexapro , Zoloft) can be effective as well . Reports in the literature suggest that the combination of meds + therapy has the greatest benefit both short and long term . Good luck
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The extraordinary difficulty you are experiencing with the taper may reflect a re-emergence of your anxiety rather that benzo withdrawal .

Meds such as sertraline can be effective treating anxiety. Once symptoms are under better control ,the taper may be possible . You and your doctor can decide how to complete this crossover and whether other psychotherapeutic interventions may be helpful.
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Trazadone at 50-100 mg is often added for sleep difficulty as it can be sedating at low dose and work as antidepressant at high dose.

Most people tolerate the medication well but watch for sleepiness/lack of alertness or lightheadedness the next day. You and your doctor can monitor how effective this combination is for your symptoms and of course , any side effects that occur.
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